User Manual

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USERS MANUAL
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Document number Revision
4/198 17-LXE 108 566 Uen PA7
3.4.5 Loudspeaker path
An application using the analog audio interface must re-reference the AFMS-signal from
AGND to its own internal BIAS. The figure shows a differential implementation. C1 is
chosen to create the correct HP frequency response. R1 and R2 determine the gain,
and C2 and R2 determine the LP frequency response.
0
-
+
0
R1
>=10k
R1
>=10k
R2
R2
C1
C1
C2
C2
BIAS
AFMS
AGND
Internal App +
Internal App -